脊髓小脑共济失调2型家系ATXN2基因中间重复病例表型与分子遗传学特征

目的探讨脊髓小脑共济失调2型(SCA2)致病基因ATXN2异常等位基因中间重复个体的表型和分子遗传学特点。方法针对2005—2018年中日友好医院神经科运动障碍与神经遗传病研究中心收集的1383个常染色体显性遗传共济失调家系的先证者和部分家系成员,采用荧光标记毛细管电泳片段分析方法进行动态突变检测,对携带ATXN2基因中间重复的个体进行临床表型和遗传特征分析。结果共检出163个家系(包含先证者和家系成员共203人)携带异常扩展的ATXN2基因CAG重复序列,其中93个家系中有107例的异常扩展等位基因重复次数在29~34次之间。在其中的20个亲子对中,父系遗传16个,异常等位基因的代间扩展增加0~28次,母系遗传4个,异常等位基因的代间扩展增加0~4次。结论对于临床拟诊SCA2家系患者,需对其亲代或成年子代个体进行ATXN2基因检测,以免漏诊。动态突变基因检测有助于识别中间重复的个体,对明确家系致病基因和遗传咨询至关重要。     

miR-149与肿瘤关系的研究进展

miRNAs是一类长度约为20~25个核苷酸，参与基因调控表达的内源性非编码RNA。miR-149作为miRNAs的重要成员，在多种肿瘤中表达异常，其表达水平与肿瘤细胞增殖、转移、凋亡、耐药、患者的早期诊断及预后密切相关。因此，miR-149有望成为新一类抗肿瘤治疗的靶点。     

学龄期近视进展儿童调节功能的客观检查和分析

目的　对学龄期近视进展儿童进行调节功能的客观检查与分析，观察调节功能与近视进展之间的相关性。方法　选取2017年至2018年在首都医科大学附属北京同仁医院视光学门诊定期就诊的71名学龄期儿童为研究对象，根据受试者近年的屈光度进展速度，按≤0.50 D·a^-1、>0.50~1.00 D·a^-1、>1.00~1.50 D·a^-1、>1.50 D·a^-1分为4组，使用人眼调节分析仪对受试者进行调节功能的客观测量与分析，记录不同调节刺激视标下4组的客观调节反应值和客观调节微波动值，并作对比。结果　在所有调节视标上，各组随着调节刺激幅度增加，客观调节反应值也逐渐增加，4组在不同调节刺激视标下的客观调节反应值及平均的客观调节反应值差异均无统计学意义（均为P＞0.05）。≤0.50 D·a^-1、>0.50~1.00 D·a^-1、>1.00~1.50 D·a^-1、>1.50 D·a^-1近视进展速度组调节微波动值分别为（62.2±5.6）D、（62.5±5.3）D、（66.5±6.0）D和（58.0±6.5）D，4组间差异有统计学意义（F=6.424，P=0.001），在+0.50~-0.50 D、-2.00 D调节刺激视标下，4组的客观调节微波动值比较差异均有统计学意义（均为P＜0.05），在其余调节刺激视标下差异均无统计学意义（均为P＞0.05）。结论　对于学龄期儿童的近视进展速度，客观调节微波动值相对于客观调节反应值可能是一个更为敏感的相关指标。     

Troubled-Cell Indicator Based on Mean Value Property for Hybrid WENO Schemes

In this paper, we introduce a new type of troubled-cell indicator to improve hybrid weighted essentially non-oscillatory (WENO) schemes for solving the hyperbolic conservation laws. The hybrid WENO schemes selectively adopt the high-order linear upwind scheme or the WENO scheme to avoid the local characteristic decompositions and calculations of the nonlinear weights in smooth regions. Therefore, they can reduce computational cost while maintaining non-oscillatory properties in non-smooth regions. Reliable troubled-cell indicators are essential for efficient hybrid WENO methods. Most of troubled-cell indicators require proper parameters to detect discontinuities precisely, but it is very difficult to determine the parameters automatically. We develop a new troubled-cell indicator derived from the mean value theorem that does not require any variable parameters. Additionally, we investigate the characteristics of indicator variable; one of the conserved properties or the entropy is considered as indicator variable. Detailed numerical tests for 1D and 2D Euler equations are conducted to demonstrate the performance of the proposed indicator. The results with the proposed troubled-cell indicator are in good agreement with pure WENO schemes. Also the new indicator has advantages in the computational cost compared with the other indicators.     

Severe lumbar spinal stenosis combined with Guillain-Barré syndrome: A case report

BACKGROUNDGuillain-Barré syndrome (GBS) is a rare disorder that typically presents with ascending weakness, pain, paraesthesias, and numbness, which mimic the findings in lumbar spinal stenosis. Here, we report a case of severe lumbar spinal stenosis combined with GBS.CASE SUMMARYA 70-year-old man with a history of lumbar spinal stenosis presented to our emergency department with severe lower back pain and lower extremity numbness. Magnetic resonance imaging confirmed the diagnosis of severe lumbar spinal stenosis. However, his symptoms did not improve postoperatively and he developed dysphagia and upper extremity numbness. An electromyogram was performed. Based on his symptoms, physical examination, and electromyogram, he was diagnosed with GBS. After 5 d of intravenous immunoglobulin (0.4 g/kg/d for 5 d) therapy, he gained 4/5 of strength in his upper and lower extremities and denied paraesthesias. He had regained 5/5 of strength in his extremities when he was discharged and had no symptoms during follow-up.CONCLUSIONGBS should be considered in the differential diagnosis of spinal disorder, even though magnetic resonance imaging shows severe lumbar spinal stenosis. This case highlights the importance of a careful diagnosis when a patient has a history of a disease and comes to the hospital with the same or similar symptoms.